Fluid-pressure brake.



W. V. TURNER.

FLUID PRESSURE BRAKE.

APPLIOATION FILED NOV. 2a, 1908.

1,096,870. Patented May 19, 1914.

2 SHEETS-SHEET 1. 27 1.6.

Sen/fee 4 WITNESSE mvcm'on W. V. TURNER.

FLUID PRESSURE BRAKE.

APPLIOAITION FILED NOV. 28, 190B.

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7 I 8 V. 6 a 9 I 11 R O T N E V N WITNESSES W/ Att'y.

WALTER v. TURNER, or nnenwoon,

PENNSYLVANIA, ASSIGNOR TO THE WESTING- HOUSE AIR BRAKE COMPANY, OFPITTSBURGH, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

FLUID-PRESSURE BRAKE.

Specification of Letters Patent.

Patented May 19, 1914:.

Application filed November 28, 1908. Serial No. 464,974.

equipment comprises a reservoir of large capacity supplied withcompressed air in any desired ananner, an application and release valvemechanism operated bythe variation of fluid pressure in theindependenttrain pipe line for controlling the supply of air under pressure to andits release from the brake cylinder, and an emergency valve deviceadapted to operate under a reduction in pressure in the automatic oremergency train pipe line to supply air under pressure to theapplication valve mechanism, and to cut oil communication to theindependent train pipe line, the independent train pipe being normallyat atmospheric pressure when the brakes are released, and a motormansbrake valve being employed to supply air under pressure to and releasethe same from said independent trainpipe to effect the pplication andrelease of the brakes. With this prior construction ap lied to a trainof severalcars,

the indepen ent train pipe line extending therethrough and beingconnected by flexicars, in the and inasmuci as the brake cylinderpressure corresponds with the independent train pipe pressure, it isimportant that the same should not be reduced by leakage during anapplication of the brakes.

One of the objects of my present invention therefore is to provide amaintenance valve device for-the independent train pipe which shalloperate to automatically maintain the pressure in'said pipe at thedesired degree to which such pressure is set in making the application,regardless of the leakage that may occur therein. This valve device mayalso be designed to control the sup- .ply of air under pressure to theindependent valve; Fig. 9 a .brake system as applied to a single car, or

tram pipe, in making a brake application, in such a manner that the rateof increase in such pressure, and consequently the speed of applicationof the brakes shall be substantial ly. constant with difi'erent lengthsof train, and this comprises another important feature of my invention.By means of this feature of my improvement, this form of brake equipmentmay be successfully employed on trains -of various lengths from one to alarge number of cars, and the rate of application of the brakes will besub-. stantially uniform in all cases and may ,be about equivalent tothe control upon a single car. This feature also applies to the releaseof the brakes since the valve mechalllSlll may also be designed to givea substantially uniform rate of release regardless of the number of carsin the train.

Another feature of my invention relates to the emergency valve deviceand comprises means operated thereby under a reduction in automatictrain pipe pressure, for opening a local vent from the automatic trainpipe to the atmosphere, brake, cylinder, or elsewhere, in order toaccelerate the action of the valves in emergency applications.

In the accompanying drawings, Figure 1 is a diagrammatlc illustration ofa brake system embodying my improvements and adapted to be applied to atrain of three cars, two motor cars and an intermediate trailer car;Fig. 2 a sectional view of my improved maintaining and control valvedevice for the independent train pipe, the brake valve beingshownassociated directly therewith and also in section; Fig. 3 a plan of therotary valve seat of the brake valve; Fig. 4; a face view of the rotaryvalve; Figs. 5, 6, 7 and 8 diagrams illustrating the relative )ositionsof the ports in the rotary valve audits seat in the respectivepositions, release lap service, and emergency, of the brake diagrammaticview of a vehicle, and showing a modification in which the maintainingand control valve device is separated from the brake valves butconnected thereto by pipes, a single control valve device being employedfor both brake valves, Fig. 10 a sectional. view of the up plication andrelease valvemechanism and the emergency valve device, the section ofthe emergency valve seat being taken substantially on the line w-w ofFig. 11; Fig.

11 a planof the emergency slide valve seat;

7 and Fig. 12 a face View of the'emergency slide valve.

While my improvements are-adapted to be used on railway vehicles invarious classes of service I have illustrated the same in Fig. '1 asapplied in electric traction service 1n which the brake equipmentof amotor Tcarmay comprise a motor-driven air compressor -1, reservoir 2connected by pipe 3 with the motormans brakevalve 4:, the

maintaining and control valye device 5 and the applicationand-emergencyvalve mechanism, 6, the automatic train pipe or emergencyline 7 connected to thebrake valve and the emergency valve, theindependent train pipe line 8 connected to the control valve device 5-and the application valve trailer cars, may be supplied through theautomatic or emergency train pipe line 7. With this type of brake systemas described o in the prior pending application above referred to, airunder pressure is supplied through the motormans brake valve to theindependent train pipeline in making an application of the brakes, thepressure, being raised to the desired degree in the independent trainpipe and on the application valve mechanism, operates the same'to supplya correspondlng pressure to the brake cylinder. In order to maintainthis desired degree of pressure in the independent train pipe, andprevent reduction therein due to leakage during the time that the brakesremain applied, l'provide means such as a chamber in which this desireddegree of pressure is held substantially constant, and a valve devicegoverned by the pressure of said chamber forcontro-lling the supply ofair to the independent train pipe so as to compensate for any leakagetherein. and

automatically maintain the pressure constant. As shown in Fig. 2 of thedrawing,

such a construction may comprise a chamber orreservoir llcom-municatingwith the space above the piston or movable abutment 23 which operates asupply valve 27 for controlling the supply of air from a source, such asa main. reservoir pipe 3, to the independent rain pipe '8 which is infree open communication with the chamber 24 below the piston 23.Anyisuitable or preferred means may be employed foradmitting the desiredpressure to the chamber or reservoir 11. I

According to the preferred construction the maintaining valve device isso connected up with the brake valve as to also serve to control thesupply of air to the independent train pipe in making serviceapplications may be done, as shown in sheet 1 of the drawing, byproviding a brake valve 4 having a restricted port lficommumcatmg withthe control or maintaining chamber 11. In

this particular instance the brake valve seat is also provided with port14 communicating with the automatic or'emergency pipe-v line 7 and anexhaust port 16 leading to the atmosphere, while the rotary valve 12 hasthrough-ports 13, 21 and 22, and alarge cavity having ports 17, 18,19and 20 in the face of the valve.

may be directly connected to each brake valve as illustrated in Figs" 1and 2 of the 2 drawing, or if desired a single valve device may beemployed and connected to the two brake valves of a motor car by pipeconnections as illustrated in Fig. 9. In either case the chamber abovethe rotary valve 12 of the brake valve communicates with the source ofsupply or main reservoir pipe 3. The maintaining and control valvedevice may also serve to govern the discharge'or release of air from theindependent train pipe, and for this purpose I provide anexhaust valve26 operated by the stem 25 of the piston 23 and controlling the exhaustport 28. The device then operates as follows: With the brake'valve innormal release position as illustrated in Fig. 5, air from the source ofsupply flows through ports 13 and 1 1 to'the emergency train pipe linekeeping the same, and reservoirs on trailer cars, normally charged withair under the desired degree of pressure, as described in my priorapplication above referred to. In this position the port 15 is open tothe atmosphere through cavity 17 and exhaust port 16 so that all airunder pressure is released from maintaining chamber 11. The independenttrain pipe-8 is also open to the atmosphere through chamber 24 andexhaust port 28, and the brakes are released. To make a'serviceapplication the brake valve is turned to service position, illustratedin Fig. 7, in which air is admitted through a restricted portor'passage, such as 13-15 to the. maintaining "chamber above piston 23.The pressure then increases in the maintaining ghamber at apredetermined rate, depending upon its volume and the size of therestricted inlet, and acting on piston 23 moves the same to open theapplication or supply valve 27 a suflicient amount so that the air fromthe source of supply or main reservoir pipe 3 shall flow to the inde"pendent train pipe 8 and increase the pres, sure therein and in chamber24 on the opposite side of piston 28 at substantially the same desiredrate. In this manner it will be apparent that air will be supplied tothe A maintaining and control valve'device pipe 10, and raises thepressure mo em independent train pipe either more or less rapidlyaccording to its volume or length, corresponding to the number of cars,so that the rate of rise in pressure shall be substantially equal to therate of increase in the maintaining chamber and regardless of the lengthof train.

lVhen the desired degree of pressure has been admitted to themaintaining chamber, the brake valve is turned to lap position,illustrated in Fig. 6, in which the port 15 is closed. The pressureinthe independent train pipeand inchamber 24 on the under side of piston23 then being substantially equal to that in the maintaining chamber onthe upper side of said piston, the spring 29 moves the valve and pistonupward a sufficient distance to close valve '27 but does not open theexhaust port 28 which is still covered by the slide valve 26. Thepressure thus admitted to the independent train pipe then operates uponthe piston 30 of each of the application valve mechanisms 6 throughoutthe train to apply the brakes as fully described in my prior applicationabove referred to, as follows :The air from the independent train pipe 8fiowsthrough cavity 39 of valve 38 of the emergency valve device andport 40 to the cylinder of piston 30, moving same and stemj31 to actuatevalve 32 to close exhaust ports 33, and toopen supply valve 34,whereupon air from the main reservoir pipe 3, or source of supply, flowsto the brake cylinder 9 through herein and on the opposite side ofpiston 3 .to the desired degree, and the supply valve 34 then closes.

It will be noticed that in both service and lap positions of the brakevalve that communication is open from the supply to port 14 and theemergency train pipe 7 whereby the pressure therein is maintained at thedesired degree. It will now be apparent that the brakes will be appliedin substantially the same time gregardless of the number of cars in thetrain, and if there should be any reduction in pressure in the,independent train pipe, due to leakage at 'hose connections orelsewhere, while the brakes remain applied, the pressure in themaintaining chamber, which remains constant, will immediately actuatethe piston 23 and supply valve 27 to compensate for any such leakage andmaintain the pressure in the independent train pipe constant. The brakesmay then be wholly or partially released by turning the brake valve torelease position, Fig. 5, and discharging any desired amount of airfrom; the independent train pipe as will be readily understood, thebrake valve being operated to full release and lap positions alternatelyfor grading down the pres sure of the independent train pipe and thebrake cylinders. It will also be evident that the release of the brakeswill be eilected at a substantially uni-form rate corresponding with thedischarge from the maintaining chamber.

An emergency application of the brakes may be made by turning the brakevalves to emergency position, Fig. 8, in which a large opening is madefrom the automatic train pipe 7 and port 14: through ports 19 and 17 ofthe cavity in the rotary valve and from the maintaining chamber throughports 15 and 20 to the exhaust port 16, thereby venting the emergencytrain line to the atmosphere and causing the operation of the emergencypistons 35 and valves 38 to close the independent train pipe and supplyair to the application piston. 30 to apply brakes as before described.In order to accelerate the emergency application of the brakes I haveprovided means operated by the movement of the emergency piston to opena local vent from the emergency train line to the atmosphere, brakecylinder or elsewhere,- and thereby propagate quick a'ction of thevalves through the train, and as shown in Fig. 10, this means comprisesthe additional ports 41 and 43 adapted to be pressure is vented from theemergency train pipe 7 which communicates with the chamher above theemergency piston 35, the pressure from. the reservoir which communicatesthrough passage 37 with the valve chamber on the opposite side of thepiston, moves the same up against the gasket, closing feed groove 36 andactuating the valve 38 to cut oil communication from the inde-. pendenttrain pipe 8 to port 40, to open communication from the reservoirthrough ports 37 and 40 to the piston 30 of the ap plication valve,'andto open communication from the emergency train pipe to the vent port.The check valve 42 prevents back How of air from the reservoir to -theemergency train pipe. It is also obvious that a similar emergency actionof the apparatus will be produced by-a bursted hose in the emergencytrain pipe line or by a pulling apart of the cars of the train, and itis further apparent that by reason "of my present pressure isadmittedfor making an application of the brakes, and a valve mechanismoperated by said train pipe pressure for controlling the supply of airto a brake cylinder, of a maintaining chamber or reservoir, means forincreasing the pressure in said chamber at a predetermined rate and avalve device governed by the pressure of said maintaining chamber for.supplying air to said train pipe to maintain the pressure therein. i

3. In a fluid pressure brake, the combination with a train pipe normallyat atmospheric pressure, means for admitting air under pressure to saidtrain pipe to apply brakes, and a valve mechanism subject to said trainpipe pressure for controlling the supply of air under pressure to abrake cylinder, of an automatic. valve device subject on opposite sidesto fluid pressure for maintaining the train pipe pressure againstleakage when the brakes are-held applied and means for increasing thefluid pressure on said valve device at a predetermined rate.

4:. In a fluid pressure brake, the combination with a train pipe lineinto which air I under pressure is admitted When applying brakes, and avalve mechanism operated by pressure. in said train pipe for'controlling the supply of air to a brake cylinder, of a maintainingchamber or reservoir, means for increasing thepressure in said chamberat a predetermined rate, and a valve device governed by the opposingpressures of said .chamber and the train pipe for supplying air to thetrain pipe.

5; In a fluid pressure brake, the combination with train pipe into whichair under pressure is admitted to apply brakes, and a valve mechanismsubject to said train pipe pressure for controlling the supply of -airunder pressure to a brake cylinder, of a maintaining chamber adapted tocontain the desired degree of pressure, means for increasing thepressure in said chamber at a predetermined rate, a movable abutmentsubject to the opposing pressures of the train pipe and'said chamber,and a valve means operated by saidabutment for controlling the supply ofair to the train pipe.

6. In a fluid pressure brake, the-combination with a train pipe intowhich air under pressure is admitted in applying brakes, a valvemechanism subject to said train pipe a brake cylinder, and a maintainingand control chamber with means for increasing the pressure therein at apredetermined rate,

of a valve device operated by the opposing pressures of said chamber andthe train pipe for controlling the supply of air to said train pipe.v

8. In a'fluid pressure brake, the combina:

tion with a train pipe normally at atmosphericlpressure and a valvemechanism operated by the pressure in said train pipe-for controllingthe supply of air to a brake cylinder, of a control chamber, a brakevalve havingmeans for admitting fluid under. pressure to said chamber ata predetermined rate, and a valve device operated by the pressure insaid chamber for controlling the supply of air to said train pipe.

- 9. In a fluid pressure brake, the combination with a train pipenormally at atmospheric pressure and a valve mechanism operated by thepressure in said train pipe for controlling the supply of'air to a brake,cyl

inder, of a control chamber, a brake valve for controlling the supply offluid under pressure to and its release from said cham, berat apredetermined rate, and a valve device subject to the pressure in saidchamber forcontrolling the supply of air to and its release from saidtrain pipe.

- 10. In a fluid pressure brake, the combina- I tion with a train pipenormally at atmosphericpressure and a valve mechanism 0perated by thepressure in said train pipe for controlling the supply of air to a brakecyl inder, of a control chamber, a brake valve for controlling theadmission of fluid under pressure to said chamber at a predeterminedrate, and a valve device operated by the opposing pressures of the trainpipe and said chamber'for controlling the supply of air .:to said trainpipe.

11. In a fluid pressure brake, the combination with a train pipenormally carrying air at atmospheric pressure, a control chamber havinga restricted inlet port or passage, and a brake valve for controllingsaid inlet passage, of avalve device-operated by the pressure in saidchamber for controlling tl1e-sup+ ply of air to said train pipe, and avalve" mechanism operated by the train pipe pressure for controlling thesupply of air to the brake cylinder.

12. In a fluid pressure brake, the combination with an independent trainpipe line normally at atmospheric pressure and an emergency train pipeline normally carrying air under pressure of an application valvemechanism governed by the independent train pipe pressure forcontrolling the supply of air to a brake cylinder, and an emergencyvalve device operating upon a reduction in emergency train pipe pressureto supply air to the application valve mechanism, to close communicationfrom the independent train pipe to said application valve mechanism, andto open a local ventfrom the emergency train pipe.

13. In a fluid pressure brake, the combination with a train pipe lineinto which air under pressure is admitted when applying brakes, and avalve mechanism operated by pressure in said train pipe for controllingthe supply of air to a brake cylinder, of means for supplying fluid tosaid train pipe line to increase the pressure therein at a predeterminedrate regardless of the length of the train.

In testimony whereof I have hereunto set my hand.

WALTER V. TURNER.

Witnesses:

l/VM. M. CADY, A. GLEMENTS.

